The right way to draw a nail is simply starting off by drawing the finger. NEVER draw a finger pointed, it doesn't matter if you're trying to make the finger seem to be the nail combined within. You need to give the finger depth and realism. Do you know anyone in person that has pencil fingers? There are so many ways to draw nails, that's it's impossible to draw them all! Think off all the diseases that these can become acquainted with. How about some sharp claws for fingers? What about a chipped and brittle fingernail for your creepy and sickly character? All of these traits create volume for your character. Be on the lookout for different styles and ways to design these pieces of flesh.